Now Canadian experts have identified new DNA techniques and evidence has been sent to them from West Yorkshire.

On the anniversary of Lindsay’s body being found, Det Supt Simon Atkinson said: “Our Canadian colleagues are doing some ground-breaking forensic work, so we’ve sent some of the forensic exhibits over to them.

“They have been able to develop a DNA profile which we are really interested in developing further.”

He added: “It’s a leap forward we haven’t had in the past 21 years, so I’m really excited about this development.”

Lindsay’s younger sister Juliet has spoken for the first time about her sibling’s death

Detective Superintendent Simon Atkinson

Lindsay left her home in Cambridge Street at about 10pm and visited the Trades Club in Home Street.

The last known sighting of her was caught on CCTV 20 minutes later as she bought cornflakes at a shop in Crown Street.

Her body, which had been weighted down with a stone, was recovered about a mile upstream from the town centre.

Juliet said: “A piece of everyone’s soul is missing and I often wonder how our lives would have been, if we were not a broken family.

“The advice Lindsay would have given me, the fights we might have had, and the things we may have shared.

“Getting the answers wouldn’t change the hurt, but it would help bring closure to us all.”

(Photo: West Yorkshire Police)

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